I would advise to do this with a low amount of petrol in the tank, i also unscrewed the fuel cap to release the pressure...

Ok first you have to take out the bottom part of the back seat, which is clipped in at the front... Just get your hands either side of the clip under the seat and pull up and it pops off... Then unscrew the 3 black platic nuts (10mm socket) and lift up the plate....

Carefully pull back the yellow clip a small bit and pop it out each side using a thin screwdriver, once the clips out you can pull up the black pipe ( put some rags around the area and over the pipe as when it comes off it squirts a bit of petrol)... The grey plug you see is awkward to get out because of the clips (shown in pics with red arrows), so i waited until i unscrewed and lifted the black plate which made it easier.....

Unscrew the 8 nuts you see (8mm socket) and now you can lift up the black plate... Now it's easier to remove the grey plug, unless you already managed it... Now the black plate is off you can carefully manoeuvre the full unit out of the tank... Now unclip the fuel pipe and the unit is free...

I layed down an old towel to take the unit apart... This bit has too many steps to explain in detail, but basically the plastic housing is all clipped together, so i used a thin screwdriver to carefully prise it apart.... Once the plastic housing is off prise off the star washer (i used a strong needle) and pop off the arm that's covered in mesh... Then unclip and pull the bottom pipe out of the filter and the same with the top part of the unit (both are quite stiff, but with a bit of persausion they'll pop out... When i pulled the top part of the unit out of the filter, the rubber washer and plastic yoke stayed inside the filter, so pick them out with small screwdriver and place them back on the top pipe of the unit.... (which i hightlighted on the pics with red arrow).... Now you can pull othe pump out of the filter and begin reassembling with the new filter